Spelling fixes supplied by Rob W. W. Hooft. All these are fixes in either
comments, docstrings or error messages. I fixed two minor things in
test_winreg.py ("didn't" -> "Didn't" and "Didnt" -> "Didn't").

There is a minor style issue involved: Guido seems to have preferred English
grammar (behaviour, honour) in a couple places. This patch changes that to
American, which is the more prominent style in the source. I prefer English
myself, so if English is preferred, I'd be happy to supply a patch myself ;)
diff --git a/Lib/pprint.py b/Lib/pprint.py
index 346c70b..8e10e9d 100644
--- a/Lib/pprint.py
+++ b/Lib/pprint.py
@@ -4,7 +4,7 @@
 #  This is a simple little module I wrote to make life easier.  I didn't
 #  see anything quite like it in the library, though I may have overlooked
 #  something.  I wrote this when I was trying to read some heavily nested
-#  tuples with fairly non-descriptive content.  This is modelled very much
+#  tuples with fairly non-descriptive content.  This is modeled very much
 #  after Lisp/Scheme - style pretty-printing of lists.  If you find it
 #  useful, thank small children who sleep at night.